Vehicle suspension stabilising arrangement

ABSTRACT

A stabilizing arrangement ( 100 ) characterized by a mounting member ( 32 ), at least one forward truck ( 34 ) supporting a forward pair of surface engaging members ( 36 ), and at least one rear truck ( 38 ) supporting a rear pair of surface engaging members ( 40 ), each truck ( 34, 38 ) allowing biased rotation about a central axis thereof, the forward truck ( 34 ) being mounted on the mounting member ( 32 ) such that it projects forwardly thereof and the rear truck ( 38 ) being mounted on the mounting member ( 32 ) such that it projects rearwardly thereof, and whereby the mounting member ( 32 ) is supported substantially between the trucks ( 34, 38 ) and pairs of surface engaging members ( 36, 40 ). A suspension and steering arrangement is also provided.

This application is a §371 of PCT Application Serial No. PCT/AU02/01000,filed Jul. 26, 2002.

FIELD OF THE INVENTION

The present invention relates to a stablising arrangement.

The stabilising arrangement of the present invention has application asa suspension and steering arrangement for a vehicle. Further, thesuspension and steering arrangement of the present invention is intendedfor use in providing both substantially smooth transition over uneventerrain and a tight turning circle without sliding for the vehicle orconveyance on which it is provided. It is envisaged that the suspensionarrangement of the present invention is particularly suitable for use onbicycles and motorcycles but is not to be limited thereto.

The stabilising arrangement of the present invention further hasapplication as a surface engaging member or foot for use is stabilisingany number of items, including machinery and heavy equipment, on anysurface, although most advantageously on uneven surfaces.

BACKGROUND ART

Previously, attempts have made to provide either a gliding or skatingsensation when utilising a bicycle or similar vehicle or conveyance. Inthis regard reference may be had to U.S. Pat. No. 4,863,182, AustralianPatent Application 32359/89 and British Patent Application 2122557. Eachof these documents discloses a bicycle-like conveyance on which thefront-wheel, forks and handle bars have been replaced by a single pairof small wheels, for example skateboard wheels, mounted transversely ona single axle. Such an arrangement requires the rider to steer entirelyby shifting their body weight which in turn acts on a truck supportingthe axle of the pair of small wheels. Such an arrangement is difficultto operate and is often dangerous.

The dangerous nature of prior art arrangements is accentuated throughthe use of the small pair of wheels, as the small wheels are unable toride over even small obstacles. As a result, a rider encountering anobstacle at speed may be thrown forward in a dangerous manner.

A suspension arrangement that goes some way towards overcoming the aboveproblems is disclosed in International Patent Publication WO 98/57839.This document describes a suspension arrangement for a wheeledconveyance characterised by a mounting member under which is providedtwo pairs of wheels, each pair being mounted on a skateboard-type truck.As the trucks are, mounted directly under the mounting member the wheelsand trucks operate much as they would on a skateboard. An additionalbiasing means is provided which acts to bias the forward pair of the twopairs of wheels upwardly so that obstacles may be mounted safely if therider pulls upwardly on the handlebars, if the suspension arrangement isfitted to a bicycle, thereby “kicking-up” the front pair of wheels tohelp in the mounting of the obstacle.

Unfortunately, the suspension arrangement of WO98/839 has been found notto maintain the “footprint” of the pairs of wheels when undergoing tightturns, such that one of each pair of wheels has a tendency to lift offthe ground thereby often causing the wheels remaining in contact withthe ground to skid sideways. Such a circumstance can be dangerous forthe rider of the conveyance.

In the field of heavy machinery, for example cranes and diggingequipment, it is often necessary to stabilise that equipment through theuse of hydraulic rams mounted to the sides thereof. These rams are oftenmounted on extendable arms to spread load and increase stability. Therams further have a ground engaging member or foot pivotally mounted toa lower end thereof. The pivotal mounting is intended to allow someadaptation to the form of the surface on which the equipment is to besupported. However, the provision of a mounting that is pivotal aboutonly a single axis often does not allow sufficiently stable location ofthe foot on the surface, particularly on undulating, loose or slopingsurfaces.

The suspension and steering arrangement of the present invention has asone object thereof to overcome substantially the above problems of theprior art, or to at least provide a useful alternative thereto.

The preceding discussion of the background art is intended to facilitatean understanding of the present invention only. It should be appreciatedthat the discussion is not an acknowledgement or admission that any ofthe material referred to was part of the common general knowledge inAustralia as at the priority date of the application.

Throughout the specification, unless the context requires otherwise, theword “comprise” or variations such as “comprises” or “comprising”, willbe understood to imply the inclusion of a stated integer or group ofintegers but not the exclusion of any other integer or group ofintegers.

DISCLOSURE OF THE INVENTION

In accordance with the present invention there is provided a stabilisingarrangement characterised by a mounting member, at least one forwardtruck supporting a forward pair of surface engaging members, and atleast one rear truck supporting a rear pair of surface engaging members,each truck allowing biased rotation about a central axis thereof, theforward truck being mounted on the mounting member such that it projectsforwardly thereof and the rear truck being mounted on the mountingmember such that it projects rearwardly thereof, the central axis ofrotation of each truck being aligned with a longitudinal axis of themounting member, the mounting member being supported substantiallybetween the trucks and pairs of surface engaging member, wherebyrotation of the mounting member about its longitudinal axis iscompensated for.

Preferably, the mounting of the trucks to the mounting member is suchthat the central axis of rotation of at least one of the trucks isinclined from the horizontal as defined by the mounting member. Bothtrucks are preferably inclined in this manner.

Still preferably, the inclination of the or each truck is about 8°.

Preferably, the forward and rear pairs of surface engaging members arespread at least about 150 mm apart.

Still preferably, an intermediate member is attached to the mountingmember in a pivotal manner whereby a weight may be supported on thestabilising arrangement. In one form of the invention the intermediatemember is fixed to another member by way of a resiliently biasedparallelogram link.

In accordance with the present in invention there is further provided asuspension and steering arrangement for a vehicle, the suspension andsteering arrangement characterised by a mounting member, at least oneforward truck supporting a forward wheel pair, and at least one reartruck supporting a rear wheel pair, each truck allowing biased rotationabout a central axis thereof, the forward truck being mounted on themounting member such that it projects forwardly thereof and the reartruck being mounted on the mounting member such that it projectsrearwardly thereof, the central axis of rotation of each truck beingaligned with a longitudinal axis of the mounting member, the mountingmember being supported substantially between the trucks and wheel pairs,whereby rotation of the mounting member about its longitudinal axis iscompensated for.

Preferably, the mounting member is arranged to be pivotally connected toa means for steering the conveyance on which the suspension and steeringarrangement is provided. A flexibly resilient biasing means ispreferably provided within or attached to the mounting member such thatthe forward wheels are biased upwardly, and the rear wheels downwardly.

In one form of the present invention the flexibly resilient biasingmeans is provided in the form of a radial polymeric spring.

Preferably, the mounting of the trucks to the mounting member is suchthat the central axis of rotation of at least one of the trucks isinclined from the horizontal as defined by the mounting member. Bothtrucks are preferably inclined in this manner.

Still preferably, the inclination of the or each truck is about 8°.

Preferably, the forward and rear pairs of surface engaging members arespread about 150 to 300 mm apart.

The term ‘truck’ is to be understood to encompass any arrangement whichacts to cant the wheels off the vertical, longitudinal or both axes,thereby enhancing corner and camber negotiation of the steering andsuspension arrangement.

Still preferably, the trucks at least embody a centralising and shockabsorbing pivot mechanism therein, either integrally or externally.

BRIEF DESCRIPTION OF THE DRAWINGS

The stabilising arrangement of the present invention will now bedescribed, by way of example only, with reference to three embodimentsin the form of a suspension and steering arrangement for a vehicle, andthe accompanied drawings, in which:

FIG. 1 is a side elevational view of a bicycle to which a suspension andsteering arrangement for a vehicle, in accordance with a firstembodiment of the present invention is fitted;

FIG. 2 is an upper perspective view of the suspension and steeringarrangement of FIG. 1;

FIG. 3 is a side elevational view of the suspension and steeringarrangement of FIG. 1;

FIG. 4 is a side elevational view of only the mounting member and thetrucks of the suspension and steering arrangement of FIG. 1;

FIG. 5 is a side elevational view of the suspension and steeringarrangement of FIG. 1 shown with the forward truck and wheels biasedupwardly;

FIG. 6 is an upper perspective view of the suspension and steeringarrangement of FIG. 1 shown traversing an obstacle;

FIG. 7 is an upper perspective view of a suspension and steeringarrangement in accordance with a second embodiment of the presentinvention, shown without the steering member to which it would be fittedin use;

FIG. 8 is a forward upper perspective view of a suspension and steeringarrangement in accordance with a third embodiment of the presentinvention, shown without wheels provided thereon, the steering memberbeing shown only in part;

FIG. 9 is a rear upper perspective view of the suspension and steeringarrangement of FIG. 8; and

FIG. 10 is an upper plan view of the suspension and steering arrangementof FIG. 8.

BEST MODE(S) FOR CARRYING OUT THE INVENTION

In FIG. 1 there is shown a bicycle 10 comprising a frame 12, a rearwheel 14, a drive means 16 of known form, a saddle post 18, a saddle 20,a gooseneck 22 and handle bars 24. The gooseneck 22 engages the handlebars 24 and is rotatably received through a hollow neck 26 of the frame12, in known manner.

The gooseneck 22 extends through the neck 26 of the frame 12 and engagesan elongate steering member 28 which replaces the forks of knownbicycles. The steering member 28 has provided thereon a stabilisingarrangement, in the form of a suspension and steering arrangement 30 inaccordance with a first embodiment of the present invention, and is bestseen in FIGS. 2 to 6.

The suspension and steering arrangement 30 comprises a mounting member32, a forward truck 34 supporting a forward pair of surface engagingmembers or wheels 36, and a rear truck 38 supporting a rear pair ofsurface engaging members or wheels 40.

The arrangement 30 further comprises a parallelogram link 42 and a pairof intermediate members 44. The intermediate members 44 are pivotallyconnected at their lower ends to the mounting member 32 at a pivot point46.

The parallelogram link 42 comprises, on each side of the steering member28, an upper link member 48 and a lower link member 50. Each member 48and 50 is pivotally attached to both the steering member 28 and to oneintermediate member 44. In this arrangement the intermediate members 44may move in a parallel configuration with the steering member 28.

The upper link members 48 project forwardly of the intermediate members44 to which they're pivotally attached and have mounted therebetween abase 52 of a piston or ram 54. The ram 54 extends upwardly therefrom andis pivotally attached to an upper mounting member 56 extending forwardlyfrom the steering member 28. A flexibly resilient biasing means, forexample a compression spring 58, is provided about the ram 54. The ram54 and spring 58 absorb at least a portion of any shocks passed throughthe wheels 36 and 40, the mounting member 32, and parallelogram link 42generally without passing these along the steering member 28.

The mounting member 32 has provided thereon an upwardly and forwardlyprojecting rim 60 on which flexibly resilient biasing means 62, forexample a pair of springs 62 a, have one end thereof located. Theremaining ends of the springs 62 a are attached to the upper linkmembers 48 and act to draw the forward wheels 36 upwardly about thepivot point 46 when there is no load or weight on the arrangement 30,such as when a rider (not shown) of the bicycle 10 pulls upwardly on thehandle bars 24. It is to be understood that this method of biasing themounting member 32 is one of a number of possible methods that could beemployed without departing from the scope of the present invention. Forexample, a compression spring or springs may be provided between thesteering member 28 and a point rearward of the pivot point 46 on themounting member 32, thereby achieving the same result.

In FIG. 4 the nature of the mounting of the trucks 34 and 38 to themounting member 32 is shown. The spreading of transverse axles 35 of thewheels 36 and 40 forward and back of the mounting member 32 has theeffect of enlarging the ‘footprint’ of the arrangement 30 relative to a‘traditional’ mounting which would see the trucks 34 and 38 mounteddirectly under the mounting member 32.

The arrangement of FIG. 4 effectively accentuates the flexibility of thetrucks 34 and 38. Each truck 34 and 38 allows biased rotation about itscentral axis, which in the arrangement 30 is aligned along alongitudinal axis of the mounting member 32 and, generally, the bicycle10, rather than substantially vertically as is the case in thearrangement of WO 98/57839 and traditional skateboards. Further rotationis provided for about a vertical axis passing through each truck 34 and38. This orientation of the trucks allows significant rotation of thewheel axles relative to both the longitudinal and vertical axis of eachtruck, thereby allowing the footprint to remain on the ground evenwhilst the bicycle 10 is undergoing tight turns, and even whilsttraversing uneven terrain, as can be seen in FIGS. 5 and 6.

In FIG. 4 a horizontal plane is shown by line A-A, essentially definedby the transverse axles 35 and the mounting member 32. The inclinationof the mounting of the trucks 34 and 38 to the mounting member 32 can beseen in this Figure. Each truck is inclined at about 8° to thehorizontal, this angle being designated X. This acts to lower the pivotpoint 46 relative to the axles 35 of the wheels 36 and 40 andaccentuates the stability of the arrangement 30 when turning, and whentraversing uneven terrain. It is envisaged that the angle X may beprovided reasonably up to 45°, although theoretically any angle of up to90° should function in accordance with the invention.

The axles 35 of the wheel pairs 36 and 40 are spread about 150 mm apart,although it is envisaged that a spread of up to 300 mm would stillfunction appropriately. However, the size of the “footprint” must bebalanced against an ability to traverse bumps and the like without‘grounding’ the mounting member 32.

It is preferable that the pivot point 46 be located as close to the lineA-A as practical as this adds to the stability of the arrangement 30,particularly when turning.

The upper mounting member 56 and the parallelogram link 42 may belocated at any point with respect to the steering member 28 and stillfunction in accordance with the present invention. Further, thearrangement 30 may similarly be arranged as a ‘trailing link’ as opposedto the ‘leading link’ described hereinabove. In such a ‘trailing link’arrangement the parallelogram link 42 projects rearwardly of thesteering member 28.

In FIG. 7 there is shown a suspension and steering arrangement 100 inaccordance with a second embodiment of the present inventionsubstantially similar to the suspension and steering arrangement 30described hereinabove and like numerals denote like parts. The steeringmember to which the parallelogram link 42 is attached is not shown.

A lower end 102 of an intermediate member 104 is mounted on a transversemember 106 provided between the forward projections of the upper linkmembers 48. An upper end 108 of the intermediate member 104 is arrangedto be mounted to the steering member (not shown) at a point above thelevel of the mounting of the parallelogram link 42. This mounting isachieved by way of a flexibly resilient biasing means, preferably in theform of a radially flexibly resilient polymeric material. Such a biasingmeans is distinguished by a generally annular form with an outer radialsurface and an inner radial surface, the outer surface being fixed toone member and the outer radial surface fixed to another, whereby therotation of the inner surface relative to the outer surface is flexiblyand resiliently biased.

The pivot point 46 between the intermediate members 44 and the mountingmember 32 is provided with a radially flexible resilient biasing meanssuch that the forward wheel pair 36 are biased upwardly, as in theembodiment of FIGS. 1 to 6, without the need for the pair of springs 62or similar.

Further, the typical biasing means of the trucks 34 and 38 are replacedwith a radially flexible resilient biasing means, as describedhereinabove, and located about the longitudinal rotational axis of eachtruck 34 and 38. Each truck 34 and 38 is provided with an intermediatetransverse member 110 that engages the outer surface of the biasingmeans and to which a stub axle 112 from each wheel is attached. Theinner surface of the biasing means is attached to a member defining thecentral axis of the truck.

In FIGS. 8 to 10 there is shown a suspension and steering arrangement120 in accordance with a third embodiment of the present inventionsubstantially similar to the suspension and steering arrangement 100described hereinabove and like numerals denote like parts. The steeringmember to which the parallelogram link 42 is attached is again notshown.

A single intermediate member 44 is provided having a radially flexibleresilient biasing means held within a lower end 122 and a furtherradially flexible resilient biasing means held within an upper end 124thereof. The lower end 122 is received within a recess 126 in themounting member 32. A pivot member extends transversely through therecess and engages an inner surface of the biasing means therebyproviding the pivot point 46 between the intermediate member 44 and themounting member 32.

The upper link members 48 again have a transverse member 106 providedbetween their forward ends. However, a radial biasing means is providedabout the transverse member 106, the inner surface thereof. Inengagement therewith. The outer surface thereof being in engagement inthe upper end 124 of the intermediate member 44. In such a manner theshock absorbing characteristics of the ram 54 and spring 58 of thearrangement 30 are achieved without the need for another remote mountingto the steering member 28 as provided by the upper mounting member 56.Similarly, the intermediate member 104 of the arrangement 100 is notrequired.

It is envisaged by the inventor that the parallelogram link 42 may bereplaced by its functional equivalent without departing from the spiritand scope of the present invention.

It is further envisaged that an arrangement in accordance with thepresent invention may be utilised as a surface engaging element for thestabilising arrangements employed, for example, on heavy machinery andequipment. Such applications will include cranes and digging equipmentemploying rams with surface engaging elements on the lower ends thereof.The wheels of the arrangements 30, 100 and 120 described hereinabove maybe replaced with other more suitable surface engaging means.

In such applications the same features that provide the surface holdingability of the arrangements 30, 100 and 120 provide the arrangement withan ability to adapt to the configuration of a surface, be it undulatingor loose, in a stable manner. It is envisaged that the intermediatemember 44 may be attached to the piston member of a ram in the samemanner as it is described above as being attached to the steering member28. Alternatively, the ram may be attached to the mounting member 32directly.

It is still further envisaged that the surface engaging elementapplications of the arrangement of the present invention go beyondstabilising heavy equipment and may find application in othercircumstances requiring a stable ground engaging element.

The stabilising arrangements 30, 100 and 120 described hereinabove areto be understood to be an illustration of principle only. The same orsimilar functions may be achieved through the use of linkages,mechanisms or transposed elements of the spirit and nature of those ofthe embodiment described, in one or more arrangements or combinationsthereof in any area or location within or on a vehicle. As such,modifications and variations such as would be apparent to the skilledaddressee are considered to fall within the scope of the presentinvention.

1. A stabilising arrangement comprising: a mounting member, at least oneforward truck supporting a forward pair of surface engaging members, andat least one rear truck supporting a rear pair of surface engagingmembers, each truck being biasedly rotatable about a central axisthereof with respect to the mounting member, the forward truck beingmounted on the mounting member such that it extends forwardly therefromand the rear truck being mounted on the mounting member such that itextends rearwardly therefrom, the mounting member being supportedsubstantially between the trucks and pairs of surface engaging members,whereby rotation of the mounting member with respect to its longitudinalaxis is accommodated by relative movement of each truck about thecentral axis, wherein a steering member is connected to the mountingmember for turning the mounting member about an axis substantiallyperpendicular to a surface engaged by the surface engaging members.
 2. Astabilising arrangement according to claim 1, wherein the mounting ofthe trucks to the mounting member is such that the central axis ofrotation of at least one of the trucks is inclined from the horizontalas defined by the mounting member.
 3. A stabilising arrangementaccording to claim 2, wherein both trucks are inclined in this manner.4. A stabilising arrangement according to claim 2, wherein theinclination of the or each truck is about 8°.
 5. A stabilisingarrangement according to claim 1, wherein the forward and rear pairs ofsurface engaging members are spread at least about 150 mm apart.
 6. Astabilising arrangement according to claim 1, wherein an intermediatemember is attached to the mounting member in a pivotal manner whereby aforce acting toward the stabilising arrangement is supported thereby. 7.A stabilising arrangement according to claim 6, wherein the intermediatemember is also fixed to another member by way of a resiliently biasedparallelogram link.
 8. A suspension and steering arrangement accordingto claim 1, wherein the steering member is further adapted to rotate themounting member about its longitudinal axis.
 9. A suspension andsteering arrangement for a vehicle, the suspension and steeringarrangement comprising: a mounting member, at least one forward trucksupporting a forward wheel pair, and at least one rear truck supportinga rear wheel pair, each truck being biasedly rotatable about a centralaxis thereof with respect to the mounting member, the forward truckbeing mounted on the mounting member such that it extends forwardlytherefrom and the rear truck being mounted on the mounting member suchthat it extends rearwardly therefrom, the mounting member beingsupported substantially between the trucks and wheel pairs, wherebyrotation of the mounting member with respect to its longitudinal axis isaccommodated by relative movement of each truck about the central axis,wherein a steering member is connected to the mounting member forturning the mounting member about an axis substantially perpendicular toa surface engaged by the surface engaging members.
 10. A suspension andsteering arrangement according to claim 9, wherein the mounting memberis arranged to be pivotally connected to a means for steering aconveyance on which the suspension and steering arrangement is provided.11. A suspension and steering arrangement according to claim 9, whereina flexibly resilient biasing means is provided such that the forwardwheels are biased upwardly, and the rear wheels downwardly.
 12. Asuspension and steering arrangement according to claim 11, wherein theflexibly resilient biasing means is provided in the form of a springmade of a polymeric material.
 13. A suspension and steering arrangementaccording to claim 9, wherein the mounting of the trucks to the mountingmember is such that the central axis of rotation of at least one of thetrucks is inclined from the horizontal as defined by the mountingmember.
 14. A suspension and steering arrangement according to claim 9,wherein the steering member is further adapted to rotate the mountingmember abouts its longitudinal axis.